Ditto Dat^^^
....and depends on the person doing the work, and other parts of their lives, if it's overwhelming or not.
@Cierabug I see from your other threads that you appear to be a fairly new chicken keeper with aspirations of being an 'egg farmer' and are doing your homework for various aspects of such an endeavor. Start smaller, not 500, get some experience under your belt with taking care of and housing the birds you have now, as well as your market and the regulations for selling eggs in your area. After a year or two, you'll have the answers to your question of how much time it takes to care for more.
Adding your location to your profile so it shows under your avatar will help people give you better information.
It's easy to do, (laptop version shown), then it's always there!
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